Shell script learning-2

1. Use shell programming to determine whether a file is a block or character device file. If it is copied to the/dev directory.

#! /Bin/bash
# 1.sh
# Determine whether a file is a character or a block device file. If it is copied to the/dev directory
# File executable: chmod 755 1.sh
Path =/bin:/sbin:/usr/bin:/usr/sbin:/usr/local/bin:/usr/local/sbin :~ /Bin
Export path
Echo-e "the program will judge a file is or not a device file./n"
Read-P "input a filename:" filename
If [-B "$ FILENAME"-o-c "$ FILENAME"]
Then
Echo "$ filename is a device file" & CP $ filename/dev /&
Else
Echo "$ filename is not a device file" & Exit 1
Fi

 

1.5 use shell programming to determine whether all files in the directory are block or character device files. If they are copied to the/laji directory.
For file in 'LS-L/dev | awk '/^ [BC]/{print $10 }''
Do
File = "/dev/" $ File
Echo-e "$ file is block file or character file" & CP $ File/laji-RF
Done

Or

Ls-L/dev | awk '/^ [BC]/{print "/dev/" $10}' | xargs-I CP {} laji-RF

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2. Design a shell program, add a new group named class1, and add 30 users to the group. The username format is stdxx, where xx ranges from 01 to 30.

#! /Bin/bash
# 2.sh
# Design a shell program, add a new group named class1, and add 30 users to the group. The username format is stdxx, where xx ranges from 01 to 30.
# File executable: chmod 755 2.sh
Path =/bin:/sbin:/usr/bin:/usr/sbin:/usr/local/bin:/usr/local/sbin :~ /Bin
Export path
Groupadd class1
For I in {9901... 9930}
Do
Xx = 'echo $ I | SED's/99 // g''
Useradd-G class1 STD $ XX
Echo STD $ XX | passwd STD $ XX -- stdin
Echo-e "User STD $ XX password is STD $ XX">/root/newuser.txt
Done

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3. Write a shell program to automatically delete 50 accounts. The account name is stud1 to stud50.

#! /Bin/bash
# 4.sh
# Compile a shell program to automatically delete 50 accounts. The account name is stud1 to stud50.
# File executable: chmod 755 3.sh
Path =/bin:/sbin:/usr/bin:/usr/sbin:/usr/local/bin:/usr/local/sbin :~ /Bin
Export path
I = 1
While [I-Le 50]
Do
Let I ++
Userdel-r stud $ I
Done

-------------------------------
4. A system administrator needs to do some repetitive work every day. Prepare a solution according to the following requirements:
(1) Delete All subdirectories and all files under the/ABC directory;
(2) From ~ At pm, all data in the first domain of each line in the X1 file under the/XYZ directory is read to the bak01.txt file under the/backupdirectory;
(3) archive and compress all directories and files under the/data directory as files at every Monday: backup.tar.gz;
(4) uninstall the CD-ROM of the IDE interface at PM (assuming the device name of the CD-ROM is HDC );
(5) Start the instance before a.m.

In Vim/etc/crontab, add the following content:

50 16 * root Rm-RF/ABC/* 2> & 1 &
00 8-18 *** root CAT/XYZ/X1 | awk '{print $1}'>/backup/bak01.txt 2> & 1 &
50 17 ** 1 root CD/data; tar-zcvf backup.tar.gz * 2> & 1 &
55 17 *** root umount/HDC 2> & 1 &

5) Start the instance before a.m. --> I don't quite understand what it means. I don't know if it is set to start the instance before a.m, you don't need to start it after.
Run the following command.
Chkconfig -- level 2345 crond on

----------------------------

5. Design a shell program, back up and compress all the content in the/etc directory on the first day of every month, store it in the/root/bak directory, and file name
The format is yymmdd_etc. yy is year, mm is month, and DD is day. The shell program fileback is stored in the/usr/bin directory.

Vim/usr/bin/fileback. Sh

#! /Bin/bash
# Fileback. Sh
# File executable: chmod 755 fileback. Sh
Path =/bin:/sbin:/usr/bin:/usr/sbin:/usr/local/bin:/usr/local/sbin :~ /Bin
Export path
Filename = 'date when policyunci d'_etc.tar.gz
CD/etc/
Tar-zcvf $ filename *
MV $ filename/root/bak/
------------------------------------------------------
Vim/etc/crontab
** 1 ** root./fileback. Sh &

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6. What should a common user do to regularly back up/user/backup to the/tmp directory at 00:00 every Sunday?
You can use contab-E, which is similar to the above question.

7. Design a shell program and create 50 directories under the/userdata directory, that is, user1 ~ User50, and set permissions for each directory.
The permission of other users is: read; the permission of the file owner is: read, write, and execute; the permission of the group where the file owner is located is: read and execute.

#! /Bin/bash
# 7.sh
# File executable: chmod 755 7.sh
Path =/bin:/sbin:/usr/bin:/usr/sbin:/usr/local/bin:/usr/local/sbin :~ /Bin
Export path
For (I = 1; I <= 50; I ++ ))
Do
Mkdir-P/usrdata/user $ I
CD/usrdata
Chmod 754 user $ I
Done